Chromophobe cell renal carcinoma is a relatively rare primary tumour of the kidney. We present two cases of sarcomatoid transformation in this type of renal cell carcinoma. Described transformation in chromophobe renal cell carcinoma has been reported previously only in four publications. We present a very unusual aggressive recurrence of one of our cases and introduce the first case of sarcomatoid carcinoma arising from chromophobe cell renal carci- noma of the kidney with rhabdomyoblastic differentiation.

        Key words: Hes O., Michal M., Kinkor Z., Tomeš P., Zůchová M., Nápravník I.